This invention relates generally to a mechanism for adjusting a vehicle headlamp.
Ryder et al U.S. Pat. No. 4,674,018 discloses a headlamp adjusting mechanism for a modern headlamp assembly of the type in which both the high and low beam bulbs are contained in a common housing adapted to be adjusted interiorly from the vehicle engine compartment.
The Ryder et al adjusting mechanism relies on gears rotatably mounted in a housing, requires a comparatively large number of parts and is relatively expensive. Specifically, the Ryder et al adjusting mechanism includes a plastic housing in which a pair of bevel gears are mounted, one gear being connected to a screw coupled to the headlamp assembly while the other gear is associated with an adjusting screw. When the coupled gears are rotated, stress flexes the housing and causes the screws to bind in the housing so as to impair the adjusting function. Moreover, the seams and parting lines in the housing tend to open up from the forces of the gears working together and this allows moisture and grime to enter the housing and foul the mechanism.